Abstract: Proton conducting membranes having improved resistance to methanol crossover are provided, along with methods for their manufacture. In a preferred embodiment, the polymeric membranes are formed by (a) dissolving a polymer, preferably a polyphosphazene, in an organic solvent to form a polymer solution; (b) adding an oxyacid to the polymer solution; (c) optionally, adding water to the polymer solution, preferably in a molar ratio equivalent to the oxyacid; (d) optionally, concentrating the polymer solution; (e) casting the polymer solution on a casting surface, such as one formed of or coated with TEFLON™; and (f) removing the organic solvent, so as to form the polymeric membrane. A particularly useful application for these polymeric membranes is in fuel cells, such as those wherein methanol and oxygen are converted into electrical energy.

Abstract: A metal oxide layer can be deposited onto metallic or ceramic surfaces of a structure in situ, by exposing the surfaces to a precursor solution at an elevated temperature. The precursor solution contains: an organometallic, an oxidant, a surfactant, a chelating agent and water. The precursor solution is injected into the structure and maintained at a specific temperature, pH level and pressure for a predetermined period of time. The resulting in situ metal oxide layer is permanently bonded to the surface structure and does require post deposition heat treatment.